A key goal in treating patients suffering from septic shock is early detection, as well as to normalize cardiac function while maintaining optimal fluid balance. Intravenous fluid resuscitation and management is often critical to survival, but can also lead to fluid overload and potentially fatal downstream consequences. Currently there is a lack of adequate tools with which to monitor patient responses to fluid infusion, particularly those that can safely and accurately measure cardiac output or detect the onset of fluid overload. In response to this need we have developed the Canary Catheter, a pivotal, next generation technical enhancement to the current indwelling urinary catheter standard for patients admitted to the ICU. The unique system enhances the current septic shock management profile through several key characteristics: (1) Simultaneous detection and isolation of multiple key physiological parameters, (2) Non-invasive, easily accessible relative CO monitoring, (3) Continuous, accurate and real-time detection of FO, and (4) Precise monitoring with limited associated cost or ER staff burden. In the Phase 1 stage of this SBIR we succeeded in demonstrating the feasibility of measuring useful clinical variables in real time by using the Canary Catheter in the bladder of a porcine model. Specifically, we targeted clinical variables related to the development and management of sepsis (see table). Additionally, the clinicians we have worked with have been enthusiastic about the prospect that the CC may be able to also serve as an early-detection system for patients in the ICU who are at risk for developing sepsis, thus enabling earlier treatment and improvement of outcomes. Our Phase 1 feasibility data supports our current goal for this proposal, which is to discover key physiologic patterns in the prediction of sepsis onset and fluid overload management in a clinical setting. Aim 1 - Verification and Validation of the Canary Catheter for Clinical Trial. In the first subtask we will manufacture the units necessary for a 100-patient clinical study as well as for verificatio and validation testing. In addition we will complete the training the health care staff at each of our three study sites, in preparation for the study initiation. The second subtask of this aim is t refine our methods of data analysis and begin development of a predictive model for sepsis based on the Canary Catheter's measurement capabilities. Aim 2 - Discover key physiologic patterns in the prediction of sepsis onset and fluid overload management in a clinical setting. The design of the trial is a 2-year, observational, multi-center study using the Canary Catheter to collect data from 100 patients. Expected Outcomes: Detection: We expect that by providing high resolution measures of SIRS parameters into predictive models, we will be able to more quickly detect the onset of sepsis. Management: This aim will be successful if a predictive score cutoff can be identified in any of the models using IAP and rCO, either individually or in combination, providing detection of FO with both sensitivity and specificity greater than 80%.